Wind energy is increasingly recognized as a viable option for complementing and even replacing other types of energy sources such as for instance fossil fuels. In the early development of wind energy, the majority of wind turbines were constructed for operation at a constant speed. However, recently the trend is toward using variable-speed wind turbines to better capture available wind power. In most cases, wind turbine blade pitch angles can be adjusted to control the operation of the variable speed wind turbine. However, during certain wind conditions like wake, wind shear, high turbulence or ice on the blades it can cause high vibrations on the turbine r the blades. The vibration level may be monitored by G-sensors and when reaching high vibrations the turbine will be affected by larger forces and it will wear down much faster.